not familiar with the SM but i'm guessing these are the composites like schubeck?

i kinda like solids but the horror stories are scary. these days even with mild grinds i would be inclined to use tool steel EDMs. as for the composites i would tend to think they would be reserved for classes that require a solid. i have no experience with them but i guess like any other lifter if you let it flop around something breaks.